Designation C1361 − 10 (Reapproved 2015) Standard Practice for Constant Amplitude, Axial, Tension Tension Cyclic Fatigue of Advanced Ceramics at Ambient Temperatures1 This standard is issued under the[.]
Designation: C1361 − 10 (Reapproved 2015) Standard Practice for Constant-Amplitude, Axial, Tension-Tension Cyclic Fatigue of Advanced Ceramics at Ambient Temperatures1 This standard is issued under the fixed designation C1361; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision A number in parentheses indicates the year of last reapproval A superscript epsilon (´) indicates an editorial change since the last revision or reapproval Referenced Documents Scope* 2.1 ASTM Standards:2 C1145 Terminology of Advanced Ceramics C1273 Test Method for Tensile Strength of Monolithic Advanced Ceramics at Ambient Temperatures C1322 Practice for Fractography and Characterization of Fracture Origins in Advanced Ceramics E4 Practices for Force Verification of Testing Machines E6 Terminology Relating to Methods of Mechanical Testing E83 Practice for Verification and Classification of Extensometer Systems E337 Test Method for Measuring Humidity with a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures) E467 Practice for Verification of Constant Amplitude Dynamic Forces in an Axial Fatigue Testing System E468 Practice for Presentation of Constant Amplitude Fatigue Test Results for Metallic Materials E739 Practice for Statistical Analysis of Linear or Linearized Stress-Life (S-N) and Strain-Life (ε-N) Fatigue Data E1012 Practice for Verification of Testing Frame and Specimen Alignment Under Tensile and Compressive Axial Force Application E1823 Terminology Relating to Fatigue and Fracture Testing IEEE/ASTM SI 10 Standard for Use of the International System of Units (SI) (The Modern Metric System) 2.2 Military Handbook: MIL-HDBK-790 Fractography and Characterization of Fracture Origins in Advanced Structural Ceramics3 1.1 This practice covers the determination of constantamplitude, axial tension-tension cyclic fatigue behavior and performance of advanced ceramics at ambient temperatures to establish “baseline” cyclic fatigue performance This practice builds on experience and existing standards in tensile testing advanced ceramics at ambient temperatures and addresses various suggested test specimen geometries, test specimen fabrication methods, testing modes (force, displacement, or strain control), testing rates and frequencies, allowable bending, and procedures for data collection and reporting This practice does not apply to axial cyclic fatigue tests of components or parts (that is, machine elements with non uniform or multiaxial stress states) 1.2 This practice applies primarily to advanced ceramics that macroscopically exhibit isotropic, homogeneous, continuous behaviour While this practice applies primarily to monolithic advanced ceramics, certain whisker- or particlereinforced composite ceramics as well as certain discontinuous fibre-reinforced composite ceramics may also meet these macroscopic behaviour assumptions Generally, continuous fibre-reinforced ceramic composites (CFCCs) not macroscopically exhibit isotropic, homogeneous, continuous behaviour and application of this practice to these materials is not recommended 1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use Refer to Section for specific precautions Terminology 3.1 Definitions—Definitions of terms relating to advanced ceramics, cyclic fatigue, and tensile testing as they appear in Terminology C1145, Terminology E1823, and Terminology E6, respectively, apply to the terms used in this practice Selected terms with definitions non-specific to this practice This practice is under the jurisdiction of ASTM Committee C28 on Advanced Ceramics and is the direct responsibility of Subcommittee C28.01 on Mechanical Properties and Performance Current edition approved July 1, 2015 Published September 2015 Originally approved in 1996 Last previous edition approved in 2010 as C1361 – 10 DOI: 10.1520/C1361-10R15 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website Available from Army Research Laboratory-Materials Directorate, Aberdeen Proving Ground, MD 21005 *A Summary of Changes section appears at the end of this standard Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959 United States C1361 − 10 (2015) 3.2.7.1 Discussion—Certain materials and environments preclude the attainment of a cyclic fatigue limit Values tabulated as cyclic fatigue limits in the literature are frequently (but not always) values of Sf at 50 % survival at Nf cycles of stress in which the mean stress, Sm, equals zero 3.2.8 cyclic fatigue strength SN, [FL–2], n—the limiting value of the median cyclic fatigue strength at a particular cyclic fatigue life, Nf (See Terminology E1823.) 3.2.9 gage length, [L], n—the original length of that portion of the test specimen over which strain or change of length is determined (See Terminology E6.) 3.2.10 load ratio, n—in cyclic fatigue loading, the algebraic ratio of the two loading parameters of a cycle; the most widely used ratios (see Terminology E1823): FIG Cyclic Fatigue Nomenclature and Wave Forms R5 minimum force valley force or R maximum force peak force and: follow in 3.2 with the appropriate source given in parenthesis Terms specific to this practice are defined in 3.3 Α5 3.2 Definitions of Terms Non Specific to This Standard: 3.2.1 advanced ceramic, n—a highly engineered, high performance predominately non-metallic, inorganic, ceramic material having specific functional attributes (See Terminology C1145.) 3.2.2 axial strain [LL–1], n—the average longitudinal strains measured at the surface on opposite sides of the longitudinal axis of symmetry of the test specimen by two strain-sensing devices located at the mid length of the reduced section (See Practice E1012.) 3.2.3 bending strain [LL–1], n—the difference between the strain at the surface and the axial strain In general, the bending strain varies from point to point around and along the reduced section of the test specimen (See Practice E1012.) 3.2.4 constant amplitude loading, n—in cyclic fatigue loading, a loading in which all peak loads are equal and all of the valley forces are equal (See Terminology E1823.) 3.2.5 cyclic fatigue, n—the process of progressive localized permanent structural change occurring in a material subjected to conditions that produce fluctuating stresses and strains at some point or points and that may culminate in cracks or complete fracture after a sufficient number of fluctuations (See Terminology E1823.) See Fig for nomenclature relevant to cyclic fatigue testing 3.2.5.1 Discussion—In glass technology static tests of considerable duration are called static fatigue tests, a type of test generally designated as stress-rupture 3.2.5.2 Discussion—Fluctuations may occur both in load and with time (frequency) as in the case of random vibration 3.2.6 cyclic fatigue life, Nf—the number of loading cycles of a specified character that a given test specimen sustains before failure of a specified nature occurs (See Terminology E1823.) 3.2.7 cyclic fatigue limit, Sf, [FL–2], n—the limiting value of the median cyclic fatigue strength as the cyclic fatigue life,Nf, becomes very large (for example, N>106-107) (See Terminology E1823) force amplitude ~ maximum force minimum force! or Α mean force ~ maximum force1minimum force! 3.2.11 modulus of elasticity [FL–2], n—the ratio of stress to corresponding strain below the proportional limit (See Terminology E6.) 3.2.12 percent bending, n—the bending strain times 100 divided by the axial strain (See Practice E1012.) 3.2.13 S-N diagram, n—a plot of stress versus the number of cycles to failure The stress can be maximum stress, Smax, minimum stress, Smin, stress range, ∆S or Sr, or stress amplitude, Sa The diagram indicates the S-N relationship for a specified value of Sm, Α, R and a specified probability of survival For N, a log scale is almost always used, although a linear scale may also be used For S, a linear scale is usually used, although a log scale may also be used (See Terminology E1823 and Practice E468.) 3.2.14 slow crack growth, n—sub-critical crack growth (extension) that may result from, but is not restricted to, such mechanisms as environmentally-assisted stress corrosion or diffusive crack growth 3.2.15 tensile strength [FL–2], n—the maximum tensile stress which a material is capable of sustaining Tensile strength is calculated from the maximum force during a tension test carried to rupture and the original cross-sectional area of the test specimen (See Terminology E6.) 3.3 Definitions of Terms Specific to This Standard: 3.3.1 maximum stress, Smax [FL–2], n—the maximum applied stress during cyclic fatigue 3.3.2 mean stress, Smax [FL–2], n—the average applied stress during cyclic fatigue such that Sm S max1S (1) 3.3.3 minimum stress, Smin [FL–2], n—the minimum applied stress during cyclic fatigue 3.3.4 stress amplitude, Sa [FL–2], n—the difference between the mean stress and the maximum or minimum stress such that C1361 − 10 (2015) Sa S max S S max S m S m S growth which can be difficult to quantify In addition, surface or near-surface flaws introduced by the test specimen fabrication process (machining) may or may not be quantifiable by conventional measurements of surface texture Therefore, surface effects (for example, as reflected in cyclic fatigue reduction factors as classified by Marin (3)) must be inferred from the results of numerous cyclic fatigue tests performed with test specimens having identical fabrication histories (2) 3.3.5 stress range, ∆S or Sr [FL–2], n—the difference between the maximum stress and the minimum stress such that ∆S = Sr = Smax – Smin 3.3.6 time to cyclic fatigue failure, tf [t], n—total elapsed time from test initiation to test termination required to reach the number of cycles to failure 4.6 The results of cyclic fatigue tests of specimens fabricated to standardized dimensions from a particular material or selected portions of a part, or both, may not totally represent the cyclic fatigue behavior of the entire, full-size end product or its in-service behavior in different environments Significance and Use 4.1 This practice may be used for material development, material comparison, quality assurance, characterization, reliability assessment, and design data generation 4.7 However, for quality control purposes, results derived from standardized tensile test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and postprocessing heat treatments 4.2 High-strength, monolithic advanced ceramic materials are generally characterized by small grain sizes (50 Hz) that can cause internal heating (hysteresis) of the test specimen thereby affecting the cyclic fatigue life If test specimen heating is likely to occur or when there is doubt, monitor the test specimen temperature during the cycling Possible methods are: the use of radiation thermometer, thermocouples adhered to the specimen, or optical pyrometry 6.8.1 —Environmental Conditions—For ambient temperature tests conducted under constant environmental conditions, control temperature and relative humidity to within 63°C and 610 % RH, respectively Measure and report temperature and relative humidity in accordance with 9.3.5 NOTE 1—Ball-tipped or sharp-anvil micrometers may damage the test specimen surface by inducing localized cracking and, therefore, are not recommended Hazards 9.1.1 Conduct periodic, if not 100 %, inspection/ measurements of all test specimens and test specimen dimensions to ensure compliance with the drawing specifications High-resolution optical methods (for example, an optical comparator) or high-resolution digital point contact methods (for example coordinate measurement machine) are satisfactory as long as the equipment meets the specifications in 6.7 The frequency of occurrence of gage section fractures and bending in the gage section are dependent on proper overall test specimen dimensions within the required tolerances 9.1.2 In some cases it is desirable, but not required, to measure surface finish to quantify the surface condition Such methods as contacting profilometry can be used to determine surface roughness of the gage section When quantified, report the direction(s) of the surface roughness measurement and surface roughness as average surface roughness, Ra, or rootmean-square surface roughness, Rq, at a minimum 7.1 During the conducting of this practice, the possibility of flying fragments of broken test material may be great The brittle nature of advanced ceramics and the release of strain energy contribute to the potential release of uncontrolled fragments upon fracture Means for containment and retention of these fragments for safety as well as later fractographic reconstruction and analysis are recommended Test Specimen 8.1 Test Specimen Geometry—Tensile test specimens as discussed in 8.1 of Test Method C1273 may be used for cyclic fatigue testing as long as they meet the requirements of this practice and Test Method C1273 8.2 Test Specimen Preparation—Test specimen fabrication and preparation methods as discussed in 8.2 of Test Method C1273 may be used for cyclic fatigue testing as long as they meet the requirements of this practice and Test Method C1273 9.2 Test Modes and Rates: 9.2.1 General—Test modes and rates can have distinct and strong influences on the cyclic fatigue behavior of advanced ceramics even at ambient temperatures depending on test environment or condition of the test specimen Test modes may involve load, displacement, or strain control Maximum and minimum test levels as well as frequency and wave form shape will depend on the purpose for which the tests are being conducted Sine waves provide smooth transitions from maximums to minimums R ratios of 0.1 are often used for maximum amplitude effect while avoiding slack (that is loose and non-tensioned) force train Frequencies are chosen to reflect service conditions, generally ranging from to 10 Hz for exploratory tests and may extend to the 1000 Hz range for materials characterization for components In all cases report 8.3 Handling Precaution—Exercise care in storing and handling finished specimens to avoid the introduction of random and severe flaws In addition, give attention to pretest storage of test specimens in controlled environments or desiccators to avoid unquantifiable environmental degradation of specimens prior to testing If conditioning is required, condition or test the specimens, or both in a room or enclosed space maintained at 63°C and 610 % relative humidity measured in accordance with Test Method E337 8.4 Number of Test Specimens—The number of test specimens will depend on the purpose of the particular test Refer to STP 91–A as a guide to determining the number of test specimens and statistical methods C1361 − 10 (2015) from the grip interfaces Take care not to damage the fracture surfaces, if they exist, by preventing them from contacting each other or other objects Place the specimen along with any fragments from the gage section into a suitable, non-metallic container for later analysis 9.3.5 Determine and report the test temperature and relative humidity in accordance with Test Method E337 at a minimum at the beginning and end of each test, and hourly if the test duration is greater than one hour 9.3.6 Post-Test Fracture Location—Measure and report the fracture location relative to the midpoint of the gage section Use the convention that the midpoint of the gage section is mm with positive (+) measurements toward the top of the specimen as tested (and marked) and negative (–) measurements toward the bottom of the specimen as tested (and marked) the test mode, maximum test level, minimum test level, frequency, wave form, and R or Α ratio 9.2.2 Prior to cyclic fatigue testing, test a sufficient number of control specimens in accordance with Test Method C1273 STP 588 may provide guidance for the number of control specimens to test Use the average of the control tests to establish the 100 % level (that is the uniaxial tensile strength of the material) of the cyclic fatigue tests Cyclic fatigue tests can then be conducted at maximum stresses or strains as percentages of this 100 % level 9.3 Conducting the Cyclic Fatigue Test: 9.3.1 Mounting the Specimen—Each grip interface and test specimen geometry discussed in Test Method C1273 will require a unique procedure for mounting the specimen in the load train Identify and report any special components which are required for each test Mark the test specimen with an indelible marker as to top and bottom and front (side facing the operator) in relation to the test machine In the case of strain-gaged test specimens, orient the test specimen such that the front of the test specimen and a unique strain gage (for example, strain gage designated SG1) coincide 9.3.2 Preparations for Testing—Set the test mode and frequency on the testing machine Preload the test specimen to remove the slack from the force train Determine and report the amount of preload for each situation, specific to each material tensile specimen geometry If strain is being measured, either mount the extensometer on the test specimen gage section and zero the output, or, attach the lead wires of the strain gages to the signal conditioner and zero the outputs If temperature is being measured, attach the temperature recording equipment If required, ready the autograph data acquisition systems for periodic data logging NOTE 3—Results from specimens fracturing outside the uniformly stressed gage section may be considered anomalous These results from test specimens fracturing outside the gage section can still be used as censored tests (that is, tests in which a stress at lest equal to that calculated by Eq was sustained in the uniform gage section before the test was prematurely terminated by a non-gage section fracture) Censored tests are discussed in STP 91A To complete a required statistical sample for purposes of establishing cyclic fatigue behavior without censoring, test one replacement specimen for each test specimen which fractures outside the gage section 9.4 Fractography—Conduct visual examination and light microscopy to determine the mode and type of fracture In addition, although quantitatively beyond the scope of this practice, interpretive observations can be made of orientation of fracture plane and other pertinent details of the fracture surface Fractographic examination of each failed specimen is recommended to characterize the fracture behavior of advanced ceramics Fractography can be an interpretative analytical method and the guidelines established in Practice C1322 and MIL-HDBK-790, are recommended to establish objectivity 9.4.1 If fractography is conducted, it is useful, but not required to note the position of the fracture origin relative to the some position (for example, “front” or “back”) around the circumference of the specimen as inserted into the test machine or as tested This information may be useful in correlating interpreting the effect of specimen misalignment on cyclic fatigue or strength results NOTE 2—If strain gages are used to monitor bending, zero the strain gages with the test specimen attached at only one end of the fixtures, that is, hanging free This will ensure that bending due to the grip closure is factored into the measured bending In addition, if test specimen selfheating due to hysteresis is anticipated, strain gages should be temperature compensated following accepted practice 9.3.3 Conducting the Test—Initiate the data acquisition Initiate the test mode After testing has begun, check the loading often unless the testing machine is equipped with automatic load maintainers to ensure that loads at peaks and valleys not vary by greater than 1.0 % Refer to Practice E467 Mass inertia effects of the machine fixtures and specimens shall be calibrated by means of strain gages, Wheatstone bridge, and an oscilloscope or oscillograph for the particular load range and machine speed being used Corrections of loading shall be made to offset these effects and produce the desired loading cycle Refer to Practice E467 9.3.4 Record the number of cycles and corresponding test conditions at the completion of testing A test may be terminated for one of several conditions: (1) test specimen fracture; (2) reaching a pre-determined number of run-out cycles; (3) reaching a pre-determined test specimen compliance or material elastic modulus, (4) reaching a pre-determined phase lag between control mode and response At test termination, disable the action of the test machine and the data collection of the data acquisition system Carefully remove the specimen 10 Calculation 10.1 General—The basic formulae for calculating engineers parameters are given as follows Additional guidelines for interpretation and reporting cyclic fatigue results are contained in STP 91A (1), STP 588 (2) and Practice E739 10.2 Engineering Stress—Calculate the engineering stress as: σ5 P A where: σ = engineering stress, MPa, P = applied, uniaxial tensile force, N, and (3) C1361 − 10 (2015) 11.1.7 Number (n) of specimens tested validly (for example fracture in the gage section) In addition, report the total of number of test specimens tested (nT) to provide an indication of the expected success rate of the particular test specimen geometry and test apparatus, 11.1.8 Where feasible and possible, all relevant material data including vintage or billet identification As a minimum, report the approximate date the material was manufactured, 11.1.8.1 For commercial materials, where feasible and possible, report the commercial designation and lot number, 11.1.8.2 For non-commercial materials, where feasible and possible, report the major constituents and proportions as well as the primary processing route including green state and consolidation routes, 11.1.9 Description of the method of specimen preparation including all stages of machining, cleaning, and storage time and method before testing, 11.1.10 Where feasible and possible, heat treatments, coatings, or pre-test exposures, if any were applied either to the as-processed material or to the as-fabricated test specimen, 11.1.11 Test environment and intervals at which measured, including relative humidity (Test Method E337), ambient temperature, and atmosphere (for example ambient air, dry nitrogen, silicone oil, etc.), 11.1.12 Test mode (force, displacement, or strain control), wave form, actual frequency of testing and R or Α ratio, 11.1.13 Percent bending and corresponding average strain in the specimen recorded during the verification as measured at the beginning and end of the test series In addition, a curve of percent bending versus the test parameter (force, displacement, strain, etc.) is recommended to assist in understanding the role of bending over the course of testing from the minimum to the maximum 11.1.14 Mean, standard deviation, and coefficient of variation for the following measured properties of the control specimens for each test series as determined using Test Method C1273: 11.1.14.1 Tensile strength, Su, 11.1.14.2 Strain at tensile strength, εu, 11.1.14.3 Fracture strength, Sf, 11.1.14.4 Strain at fracture strength, εf, and 11.1.14.5 Modulus of elasticity, E, (if applicable) 11.1.15 The stress-life (S-N) or strain-life (ε-N) data in graphical form developed in accordance with Practices E468 and E739 An example of a stress-life (S-N) data graph for silicon nitride is shown in Fig (6), illustrating a plot of maximum stress value (S) against the number of fatigue cycles to failure (N) Alternatively or additionally, stress-time (S-tf) or strain-time (ε-tf) can be developed and presented for a test series A = original cross sectional area, mm2 The cross-sectional area A is calculated as: A w b for rectangular cross sections (4) or: A5 π d2 for circular cross sections (5) where: w = average width, b = average thickness, and d = average diameter of the gage section, mm, as detailed in 9.1 10.3 Engineering Strain—Calculate the engineering strain as: ε5 ~ l l o! lo (6) where: ε = engineering strain, l = gage length (specimen or extensometer gage length) at any time, mm, and lo = original gage length, mm In the case of strain gages, strain is measured directly and Eq is not required 11 Report 11.1 Test Set—Include in the report the following information for the test set Note any significant deviations from the procedures and requirements of this practice: 11.1.1 Date and location of testing, 11.1.2 Tensile test specimen geometry used (include engineering drawing), 11.1.3 Type and configuration of the test machine (include drawing or sketch if necessary) If a commercial test machine was used, the manufacturer and model number are sufficient for describing the test machine Good laboratory practice also dictates recording the serial numbers of the test equipment, if available, 11.1.4 Type, configuration, and resolution of strain measurement equipment used (include drawing or sketch if necessary) If a commercial extensometer or strain gages were used, the manufacturer and model number are sufficient for describing the strain measurement equipment Good laboratory practice also dictates recording the serial numbers of the test equipment, if available, 11.1.5 Type and configuration of grip interface used (include drawing or sketch if necessary) If a commercial grip interface was used, the manufacturer and model number are sufficient for describing the grip interface Good laboratory practice also dictates recording the serial numbers of the test equipment, if available, 11.1.6 Type and configuration of load train couplers (include drawing or sketch if necessary) If a commercial load train coupler was used, the manufacturer and model number are sufficient for describing the coupler Good laboratory practice also dictates recording the serial numbers of the test equipment, if available, 11.2 Individual Test Specimens—Report the following information for each test specimen tested Note and report any significant deviations from the procedures and requirements of this practice: 11.2.1 Pertinent overall specimen dimensions, if measured, such as total length, length of gage section, gripped section dimensions, etc., mm, C1361 − 10 (2015) NOTE 1—Flexure Fatigue, R = –1 (1800 cycles/min) FIG Cyclic Fatigue Behavior for HS-110 Hot-Pressed Silicon Nitride at 1800 cpm at 250, 1000, and 1200°C 11.2.2 Average surface roughness, µm, if measured, of gage section and the direction of measurement, 11.2.3 Average cross-sectional dimensions, if measured, or cross-sectional dimensions at the plane of fracture in units of mm, 11.2.4 Plots of periodic stress-strain curves, if so recorded, and corresponding cycles, 11.2.5 Maximum cyclic stress, strain, or displacement, 11.2.6 Minimum cyclic stress, strain, or displacement, 11.2.7 Amplitude of cyclic stress, strain, or displacement, 11.2.8 R or Α ratio, 11.2.9 Wave form and frequency of testing, including any hold times, 11.2.10 Cycles or time to test termination, or both, and criterion for test termination, 11.2.11 Fracture location relative to the gage section midpoint in units of mm (+ is toward the top of the test specimen as marked and — is toward the bottom of the test specimen as marked with being the gage section midpoint) if relevant, and 11.2.12 Results of fractographic examination as suggested in 9.4 12 Keywords 12.1 advanced ceramic; S-N curve; tension-tension cyclic fatigue REFERENCES (1) A Guide for Fatigue Testing and The Statistical Analysis of Fatigue Data, ASTM STP 91 A, ASTM, 1963 Alternative reference: Rice, R.C., “Fatigue Data Analysis,” ASM Handbook, Vol 8, 1985, pp 695-720 (2) Manual on Statistical Planning and Analysis for Fatigue Experiments, ASTM STP 588, ASTM, 1975 (3) Marin, J, Mechanical Behaviour of Engineering Materials, PrenticeHall, Englewood Cliffs, NJ, 1962, pp 224 (4) Jacobs, D.S and Chen, I.W.,“Mechanical and Environmental Factors in the Cyclic and Static Fatigue of Silicon Nitride,” Journal of the American Ceramic Society, Vol 77, No 5, 1994, pp 1153-1161 (5) Ueno, A., Kishimoto, H., Kawamoto, and Asakura, M., “Crack Propagation Behaviour of Sintered Silicon Nitride Unde Cyclic Load at High Stress Ratio and High Frequency,” Proceedings International Conference Fatigue and Fatigue Threshold (Fatigue ‘90), Vol 2, 1990, pp 733-738 (6) Miller, Anderson, Singhal, Lange, Diaz, and Kossosky, US Army AMMRC Center Report CTR76-32, Vol IV (AD-A060504), Dec 1976 C1361 − 10 (2015) SUMMARY OF CHANGES Committee C28 has identified the location of selected changes to this standard since the last issue (C1361 – 01 (2007)) that may impact the use of this standard (Approved July 15, 2010.) (1) Added Fig and cited it in 11.1.15 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610-832-9585 (phone), 610-832-9555 (fax), or service@astm.org (e-mail); or through the ASTM website (www.astm.org) Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http://www.copyright.com/